申論題

8. A manufacturer can produce printer paper at a cost of $2 per ream. The paper has been selling for $5 per ream, and at that price consumers have been buying 4,000 reams per month. The manufacturer is planning to raise the price of the paper and estimates that for each $1 increase in the price, 400 fewer reams will be sold each month. What price corresponds to the maximum profit? (10 points)